PROCEEDINGS OF THE FARMERS' CLUB. 189 



more than 90 percent, of its organic matter is taken up within 

 its first twelve inches, and at a depth of 34 inches the organic 

 matter will have been taken up so completely that there will be 

 no chemical trace of it in the pure and inodorous water which 

 will run out. If land is reversed to a depth of two feet, the top 

 soil, which has absorbed all the organic matter, is brought below, 

 so that the roots penetrating into it can still find pabulum there. 

 In some places a disturbance of the subsoil will destroy the crop 

 for the next year. If the subsoil contains sulphuret of iron, the 

 atmospheric action will change it into sulphate of iron which is 

 fatal to vegetation. But if we add lime, it will combine with 

 the sulphuric acid and form plaster, leaving the iron in tiie form 

 of a protoxide which is not injurious. The soil will then become 

 productive again, and more than ever before in consequence of 

 the trenching. The red shale hard pan of New Jerse}^, when 

 exposed to the atmosphere, soon crepitates into an excellent soil 

 well supplied with potash. An acre of ground cannot be trenched 

 three feet deep, thoroughly, for less than $500, unless it is done 

 with the trenching plow, and then it will cost about $70. The 

 advantages of trenching can, to a very considerable extent, be 

 obtained from underdraining and subsoil plowing. If the drains 

 are properly made and open at both ends, there is a circulation 

 of air equal to that from trenching. I plow from 12 to 15 inches 

 deep, and run a 19 inch subsoil plow below that; and if I can 

 get down 32 inches with them both, I am satisfied. I have got 

 it as deep as that for many acres, and have found it to pay. The 

 security against drought alone is a great advantage, because we 

 lose one-tenth of our produce in this country from drought. 

 Land will pay better with each successive plowing it receives at 

 $3 per day, with medium paying crops, until it has received 

 seven plowings. I think that perfect trenching is neutralized by 

 its cost. Neither trenching nor subsoiling will avail upon a 

 naturally wet soil not underdrained. 



Mr. Carpenter said that trenching had the advantage of bring- 

 ing to the surface a new soil upon whieh manure could be applied 

 with a larger percentage of profit. Upon land he had subsoiled 

 ten years ago, he could perceive no difference after the fourth 

 year ; but ground trenched ten years ago remains unchanged ; it 

 is as light now as when it was first done. When land is worth 

 $500 an acre, the soil must be deep in order that it may be useful 



